Inkjet printers that are provided with heads each having a plurality of outlets (nozzles) arranged therein and perform printing by controlling ON and OFF of ink droplet ejection from outlets while moving the heads relative to printing paper to perform scanning have conventionally been used. Also, in recent years, such inkjet printers have further reduced the size of ink droplets to be ejected and increased the density of outlet arrangement in order to print higher-resolution images.
In such inkjet printers, it is also known that unevenness can be caused in printed images due to crosstalk between outlets. In Japanese Patent Application Laid-Open No. 2009-997, in each outlet row having a plurality of outlets arranged in a width direction perpendicular to a scanning direction, the number of outlets included in each outlet group of successive outlets in the width direction that are in a non-operating state during printing are set to be 1 or more and a predetermined number or less, and the number of outlets included in each outlet group of successive outlets in the width direction that are not in the non-operating state during printing are set to be 1 or more and a predetermined number or less. This makes it possible to suppress the occurrence of unevenness due to crosstalk between outlets.
Incidentally, in an inkjet printer in which each outlet is capable of forming dots of a plurality of sizes, unintended satellite droplets (including misty droplets) or the like may be produced when a plurality of outlets in each outlet row form dots of different sizes. In this case, print quality of the inkjet printer is degraded.